Evaluation of non-endemic pemphigus foliaceus in a large series of patients: a single-center retrospective study from Turkey focuses on the relapses

Abstract Background: Pemphigus foliaceus is exceedingly rare around the world, except within the few regions where it occurs as an endemic variant. Various factors can trigger immune mechanisms that induce pemphigus foliaceus or worsen its course. Objective: To determine the demographic and clinical characteristics of the patients with pemphigus foliaceus in a large series from a non-endemic country, investigate the triggering factors, and seasonal patterns. Methods: The data of the patients diagnosed with pemphigus foliaceus in the study's center between 1989-2018 were retrospectively analyzed. Results: Sixty-eight patients (mean age, 45.7 ± 14.5 years) were included in the study. The number of onsets reached its peak in spring-summer (p = 0.008). A total of 117 relapses occurred in 42 patients and were most common in spring-summer (not significant). Specific trigger factors were detected in 45 relapses. In the other 72 relapses, the peak was observed in spring-summer (p = 0.005). There were no significant differences in the demographic and clinical variables investigated between relapsed and non-relapsed patients. Study limitations: Retrospective design. Conclusions: Triggering factors could not be identified in more than half of the relapses in the study's series. The subgroup of relapses (without identified causes), as well as the onsets of the disease, showed a significant seasonal variation with a peak in spring-summer; however, the seasonal variable did not justify the total group of relapses. Although the seasonal variation may be caused by a combination of factors, UV radiation should be considered a trigger factor for the peaks in spring-summer, particularly in Turkey.

Dermatoscopy of the Borst-Jadassohn phenomenon in hidroacanthoma simplex

Abstract The Borst-Jadassohn phenomenon is a morphological finding that consists of the presence of well-defined nests of cells located in the spiny stratum of an acanthotic epidermis. One of the neoplasms where this phenomenon is found is hidroacanthoma simplex. This neoplasm is considered the intraepidermal form of the eccrine poroma. Despite its benign nature, malignant transformations are reported. The present article reports a case of hidroacanthoma simplex and discusses the dermoscopy of this phenomenon.